Search Results

Search found 16735 results on 670 pages for 'christopher shen mu long'.

Page 9/670 | < Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >

  • Red Dot Scope Makes Sighting In Long Lenses a Snap

    - by Jason Fitzpatrick
    If you’ve ever used a high power lens, you know how tricky it can be to sight a distant subject as the field of view through the lens is so tiny. This hack takes care of that problem by using a zero-magnification red dot rifle scope. Chris Malcolm enjoys photographing birds and other wildlife with high power lenses. The problem, when shooting with huge 500mm lens and other high power lenses, is that they’re practically telescopes and acquiring a fast moving target like a bird using a through-the-lens technique is very tricky. Malcolm’s solution hinges on mounting a zero-magnification red dot rifle scope in parallel with the lens. His mock up is a bit unpolished (although we can understand not wanting to run out and buy a brand new black scope just for the experiment) but works great to get him on target. Hit up the link below to read more about his build, how be created the rail mount for the scope, and why he opted to mount it to the barrel of the lens and not the hot shoe mount on the camera. 500mm Reflex Lens with Red Dot Sight [via DIY Photography] Make Your Own Windows 8 Start Button with Zero Memory Usage Reader Request: How To Repair Blurry Photos HTG Explains: What Can You Find in an Email Header?

    Read the article

  • Refactoring a Single Rails Model with large methods & long join queries trying to do everything

    - by Kelseydh
    I have a working Ruby on Rails Model that I suspect is inefficient, hard to maintain, and full of unnecessary SQL join queries. I want to optimize and refactor this Model (Quiz.rb) to comply with Rails best practices, but I'm not sure how I should do it. The Rails app is a game that has Missions with many Stages. Users complete Stages by answering Questions that have correct or incorrect Answers. When a User tries to complete a stage by answering questions, the User gets a Quiz entry with many Attempts. Each Attempt records an Answer submitted for that Question within the Stage. A user completes a stage or mission by getting every Attempt correct, and their progress is tracked by adding a new entry to the UserMission & UserStage join tables. All of these features work, but unfortunately the Quiz.rb Model has been twisted to handle almost all of it exclusively. The callbacks began at 'Quiz.rb', and because I wasn't sure how to leave the Quiz Model during a multi-model update, I resorted to using Rails Console to have the @quiz instance variable via self.some_method do all the heavy lifting to retrieve every data value for the game's business logic; resulting in large extended join queries that "dance" all around the Database schema. The Quiz.rb Model that Smells: class Quiz < ActiveRecord::Base belongs_to :user has_many :attempts, dependent: :destroy before_save :check_answer before_save :update_user_mission_and_stage accepts_nested_attributes_for :attempts, :reject_if => lambda { |a| a[:answer_id].blank? }, :allow_destroy => true #Checks every answer within each quiz, adding +1 for each correct answer #within a stage quiz, and -1 for each incorrect answer def check_answer stage_score = 0 self.attempts.each do |attempt| if attempt.answer.correct? == true stage_score += 1 elsif attempt.answer.correct == false stage_score - 1 end end stage_score end def winner return true end def update_user_mission_and_stage ####### #Step 1: Checks if UserMission exists, finds or creates one. #if no UserMission for the current mission exists, creates a new UserMission if self.user_has_mission? == false @user_mission = UserMission.new(user_id: self.user.id, mission_id: self.current_stage.mission_id, available: true) @user_mission.save else @user_mission = self.find_user_mission end ####### #Step 2: Checks if current UserStage exists, stops if true to prevent duplicate entry if self.user_has_stage? @user_mission.save return true else ####### ##Step 3: if step 2 returns false: ##Initiates UserStage creation instructions #checks for winner (winner actions need to be defined) if they complete last stage of last mission for a given orientation if self.passed? && self.is_last_stage? && self.is_last_mission? create_user_stage_and_update_user_mission self.winner #NOTE: The rest are the same, but specify conditions that are available to add badges or other actions upon those conditions occurring: ##if user completes first stage of a mission elsif self.passed? && self.is_first_stage? && self.is_first_mission? create_user_stage_and_update_user_mission #creates user badge for finishing first stage of first mission self.user.add_badge(5) self.user.activity_logs.create(description: "granted first-stage badge", type_event: "badge", value: "first-stage") #If user completes last stage of a given mission, creates a new UserMission elsif self.passed? && self.is_last_stage? && self.is_first_mission? create_user_stage_and_update_user_mission #creates user badge for finishing first mission self.user.add_badge(6) self.user.activity_logs.create(description: "granted first-mission badge", type_event: "badge", value: "first-mission") elsif self.passed? create_user_stage_and_update_user_mission else self.passed? == false return true end end end #Creates a new UserStage record in the database for a successful Quiz question passing def create_user_stage_and_update_user_mission @nu_stage = @user_mission.user_stages.new(user_id: self.user.id, stage_id: self.current_stage.id) @nu_stage.save @user_mission.save self.user.add_points(50) end #Boolean that defines passing a stage as answering every question in that stage correct def passed? self.check_answer >= self.number_of_questions end #Returns the number of questions asked for that stage's quiz def number_of_questions self.attempts.first.answer.question.stage.questions.count end #Returns the current_stage for the Quiz, routing through 1st attempt in that Quiz def current_stage self.attempts.first.answer.question.stage end #Gives back the position of the stage relative to its mission. def stage_position self.attempts.first.answer.question.stage.position end #will find the user_mission for the current user and stage if it exists def find_user_mission self.user.user_missions.find_by_mission_id(self.current_stage.mission_id) end #Returns true if quiz was for the last stage within that mission #helpful for triggering actions related to a user completing a mission def is_last_stage? self.stage_position == self.current_stage.mission.stages.last.position end #Returns true if quiz was for the first stage within that mission #helpful for triggering actions related to a user completing a mission def is_first_stage? self.stage_position == self.current_stage.mission.stages_ordered.first.position end #Returns true if current user has a UserMission for the current stage def user_has_mission? self.user.missions.ids.include?(self.current_stage.mission.id) end #Returns true if current user has a UserStage for the current stage def user_has_stage? self.user.stages.include?(self.current_stage) end #Returns true if current user is on the last mission based on position within a given orientation def is_first_mission? self.user.missions.first.orientation.missions.by_position.first.position == self.current_stage.mission.position end #Returns true if current user is on the first stage & mission of a given orientation def is_last_mission? self.user.missions.first.orientation.missions.by_position.last.position == self.current_stage.mission.position end end My Question Currently my Rails server takes roughly 500ms to 1 sec to process single @quiz.save action. I am confident that the slowness here is due to sloppy code, not bad Database ERD design. What does a better solution look like? And specifically: Should I use join queries to retrieve values like I did here, or is it better to instantiate new objects within the model instead? Or am I missing a better solution? How should update_user_mission_and_stage be refactored to follow best practices? Relevant Code for Reference: quizzes_controller.rb w/ Controller Route Initiating Callback: class QuizzesController < ApplicationController before_action :find_stage_and_mission before_action :find_orientation before_action :find_question def show end def create @user = current_user @quiz = current_user.quizzes.new(quiz_params) if @quiz.save if @quiz.passed? if @mission.next_mission.nil? && @stage.next_stage.nil? redirect_to root_path, notice: "Congratulations, you have finished the last mission!" elsif @stage.next_stage.nil? redirect_to [@mission.next_mission, @mission.first_stage], notice: "Correct! Time for Mission #{@mission.next_mission.position}", info: "Starting next mission" else redirect_to [@mission, @stage.next_stage], notice: "Answer Correct! You passed the stage!" end else redirect_to [@mission, @stage], alert: "You didn't get every question right, please try again." end else redirect_to [@mission, @stage], alert: "Sorry. We were unable to save your answer. Please contact the admministrator." end @questions = @stage.questions.all end private def find_stage_and_mission @stage = Stage.find(params[:stage_id]) @mission = @stage.mission end def find_question @question = @stage.questions.find_by_id params[:id] end def quiz_params params.require(:quiz).permit(:user_id, :attempt_id, {attempts_attributes: [:id, :quiz_id, :answer_id]}) end def find_orientation @orientation = @mission.orientation @missions = @orientation.missions.by_position end end Overview of Relevant ERD Database Relationships: Mission - Stage - Question - Answer - Attempt <- Quiz <- User Mission - UserMission <- User Stage - UserStage <- User Other Models: Mission.rb class Mission < ActiveRecord::Base belongs_to :orientation has_many :stages has_many :user_missions, dependent: :destroy has_many :users, through: :user_missions #SCOPES scope :by_position, -> {order(position: :asc)} def stages_ordered stages.order(:position) end def next_mission self.orientation.missions.find_by_position(self.position.next) end def first_stage next_mission.stages_ordered.first end end Stage.rb: class Stage < ActiveRecord::Base belongs_to :mission has_many :questions, dependent: :destroy has_many :user_stages, dependent: :destroy has_many :users, through: :user_stages accepts_nested_attributes_for :questions, reject_if: :all_blank, allow_destroy: true def next_stage self.mission.stages.find_by_position(self.position.next) end end Question.rb class Question < ActiveRecord::Base belongs_to :stage has_many :answers, dependent: :destroy accepts_nested_attributes_for :answers, :reject_if => lambda { |a| a[:body].blank? }, :allow_destroy => true end Answer.rb: class Answer < ActiveRecord::Base belongs_to :question has_many :attempts, dependent: :destroy end Attempt.rb: class Attempt < ActiveRecord::Base belongs_to :answer belongs_to :quiz end User.rb: class User < ActiveRecord::Base belongs_to :school has_many :activity_logs has_many :user_missions, dependent: :destroy has_many :missions, through: :user_missions has_many :user_stages, dependent: :destroy has_many :stages, through: :user_stages has_many :orientations, through: :school has_many :quizzes, dependent: :destroy has_many :attempts, through: :quizzes def latest_stage_position self.user_missions.last.user_stages.last.stage.position end end UserMission.rb class UserMission < ActiveRecord::Base belongs_to :user belongs_to :mission has_many :user_stages, dependent: :destroy end UserStage.rb class UserStage < ActiveRecord::Base belongs_to :user belongs_to :stage belongs_to :user_mission end

    Read the article

  • So long wizards!

    - by geekrutherford
    In an effort to make an application more robust I have been switching to a server-side method of tracking record selections vs. client side.   The pages relying on record selections utilized the ASP.NET Wizard control which seemed like a good idea originally. Unfortunately, the design of the control is not all that flexible. It appears to want to center everything vertically which might not be a problem if it did not always use the vertical size of the largest Wizard Step for positioning.   So, I am ripping out the Wizard controls and replacing with simple Panel controls that are turned on/off. Much cleaner and presentable.

    Read the article

  • So long 2010 and Hello 2011

    - by AllenMWhite
    This has been an interesting year, one in which I had some successes and some failures. It's the first year I really worked "for myself". In the past I've had some periods between jobs where I've done some contracting, but in November 2009 I struck out on my own (with a great business partner in Shawn Upchurch). This first full calendar year in this role had its ups and downs, but overall it's been a success and I'm grateful to Shawn, my clients, and especially to my wife of 30 years, Cindi. The...(read more)

    Read the article

  • Laptop takes a long time to boot after Grub menu

    - by Andres
    I am running a Asus R401VJ laptop (Latin America version of N46VJ) that has a Core i7 CPU and 8GB RAM. After my Grub menu, which is displayed for 2 seconds as I set it up, I'm getting a black screen with a blinking white cursor that is increasing my boot time to about 60 seconds. After a while Ubuntu runs fine, I just want to reduce my boot time. I don't know if this has something to do with my never used Nvidia 2GB GeForce GT 635M graphics card. Always when I tried to install the driver, I ended up with a ~600x800 screen resolution, and I fixed it by deleting a file called: xorg.conf from the /etc/X11/ directory, following a suggestion that I read in another forum. I would appreciate detailed answers, I'm still new at Ubuntu.

    Read the article

  • Short brandable domain vs. long keyword domain

    - by bajki
    I need a counsel about my websites' domain. Let's say I have just bought two domains: xyz.com and xyzphotography.com. As we can see, the first one is shorter but way less meaningful than the second one. The second one contains a photography keyword but it's longer. I have only one website which is my photography portfolio. Can you advise me how to set those domains to make it all as SEO-friendly as possible? Which one should be the main one, does the rest should work on their own or have some kind of SEO-friendly redirect to the main domain?

    Read the article

  • login takes long time

    - by Arkaprovo Bhattacharjee
    I am using Ubuntu 12.04 from past 12 days. In the beginning login was fast enough after I put the password it hardly takes 3 to 4 sec to enter in desktop, but now its taking like more that 40 sec to show desktop after entering password. whats the problem, is there any solution? P.S there is only two programs (psensor and jupiter) that starts automatically after login. boot.log fsck from util-linux 2.20.1 /dev/sda6: clean, 254544/3325952 files, 2133831/13285632 blocks * Stopping Userspace bootsplash[164G[ OK ] * Stopping Flush boot log to disk[164G[ OK ] * Starting mDNS/DNS-SD daemon[164G[ OK ] Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox * Starting bluetooth daemon[164G[ OK ] * Starting network connection manager[164G[ OK ] * Starting AppArmor profiles [170G [164G[ OK ] * Stopping System V initialisation compatibility[164G[ OK ] * Starting CUPS printing spooler/server[164G[ OK ] * Starting System V runlevel compatibility[164G[ OK ] * Starting Bumblebee supporting nVidia Optimus cards[164G[ OK ] * Starting LightDM Display Manager[164G[ OK ] * Starting save kernel messages[164G[ OK ] * Starting anac(h)ronistic cron[164G[ OK ] * Starting ACPI daemon[164G[ OK ] * Starting regular background program processing daemon[164G[ OK ] * Starting deferred execution scheduler[164G[ OK ] speech-dispatcher disabled; edit /etc/default/speech-dispatcher * Starting CPU interrupts balancing daemon[164G[ OK ]

    Read the article

  • A rather long question about installation/uninstall

    - by user2364312
    Ok so here's the deal guys, last week I decided I want to install Ubunutu again because I really missed it. (Last time I had an ubunutu was 7.somehting) I downloaded 12.04 and isntalled it via bootable usb device. Knowing how dual boots works I cleared up some space on my hard disc before hand using the windows 7 built in disc manager. During Ubunutu's installation I thought that by choosing "Install Ubuntu alongside Windows 7" will automatically just use the space I cleared before, but apperentaly it did not since that partition is still 100% free space. On what partition is Ubunutu installed when using that method? And how can I uninstall it to re-install it back on the space I cleared up for it? Thank you very your time reading and helping!

    Read the article

  • XNA: Huge Tile Map, long load times

    - by Zach
    Recently I built a tile map generator for a game project. What I am very proud of is that I finally got it to the point where I can have a GIANT 2D map build perfectly on my PC. About 120000pixels by 40000 pixels. I can go larger actually, but I have only 1 draw back. #1 ram, the map currently draws about 320MB of ram and I know the Xbox allows 512MB I think? #2 It takes 20 mins for the map to build then display on the Xbox, on my PC it take less then a few seconds. I need to bring that 20 minutes of generating from 20 mins to how ever little bit I can, and how can a lower the amount of RAM usage while still being able to generate my map. Right now everything is stored in Jagged Arrays, each piece generating in a size of 1280x720 (the mother piece). Up to the amount that I need, every block is exactly 40x40 pixels however the blocks get removed from a List or regenerated in a List depending how close the mother piece is to the player. Saving A LOT of CPU, so at all times its no more then looping through 5184 some blocks. Well at least I'm sure of this. But how can I lower my RAM usage without hurting the size of the map, and how can I lower these INSANE loading times? EDIT: Let me explain my self better. Also I'd like to let everyone know now that I'm inexperienced with many of these things. So here is an example of the arrays I'm using. Here is the overall in a shorter term: int[][] array = new int[30][]; array[0] = new int[] { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 }; array[1] = new int[] { 1, 3, 3, 3, 3, 1, 0, 0, 0, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 }; that goes on for around 30 arrays downward. Now for every time it hits a 1, it goes and generates a tile map 1280x720 and it does that exactly the way it does it above. This is how I loop through those arrays: for (int i = 0; i < array.Length; i += 1) { for (int h = 0; h < array[i].Length; h += 1) { } { Now how the tiles are drawn and removed is something like this: public void Draw(SpriteBatch spriteBatch, Vector2 cam) { if (cam.X >= this.Position.X - 1280) { if (cam.X <= this.Position.X + 2560) { if (cam.Y >= this.Position.Y - 720) { if (cam.Y <= this.Position.Y + 1440) { if (visible) { if (once == 0) { once = 1; visible = false; regen(); } } for (int i = Tiles.Count - 1; i >= 0; i--) { Tiles[i].Draw(spriteBatch, cam); } for (int i = unWalkTiles.Count - 1; i >= 0; i--) { unWalkTiles[i].Draw(spriteBatch, cam); } } else { once = 0; for (int i = Tiles.Count - 1; i >= 0; i--) { Tiles.RemoveAt(i); } for (int i = unWalkTiles.Count - 1; i >= 0; i--) { unWalkTiles.RemoveAt(i); } } } else { once = 0; for (int i = Tiles.Count - 1; i >= 0; i--) { Tiles.RemoveAt(i); } for (int i = unWalkTiles.Count - 1; i >= 0; i--) { unWalkTiles.RemoveAt(i); } } } else { once = 0; for (int i = Tiles.Count - 1; i >= 0; i--) { Tiles.RemoveAt(i); } for (int i = unWalkTiles.Count - 1; i >= 0; i--) { unWalkTiles.RemoveAt(i); } } } else { once = 0; for (int i = Tiles.Count - 1; i >= 0; i--) { Tiles.RemoveAt(i); } for (int i = unWalkTiles.Count - 1; i >= 0; i--) { unWalkTiles.RemoveAt(i); } } } } If you guys still need more information just ask in the comments.

    Read the article

  • How long does boot repair take?

    - by Emre
    Reinstalling Ubuntu messed up my boot loader so I I tried to fix it with boot repair. It detected my OSX installation and asked about removing the "separate boot/EFI". It also said my partition was full despite the fact that it wasn't and asked me to remove stuff. I declined both and proceeded. It's been stuck at the "purge and reinstall the GRUB" stage for half an hour. Is this typical, bearing in mind I have a fast SSD and CPU? Is there a better way to re-install grub on a multi-booting UEFI system? Does my pastebin provide any insight?

    Read the article

  • Expanding on requestaudit - Tracing who is doing what...and for how long

    - by Kyle Hatlestad
    One of the most helpful tracing sections in WebCenter Content (and one that is on by default) is the requestaudit tracing.  This tracing section summarizes the top service requests happening in the server along with how they are performing.  By default, it has 2 different rotations.  One happens every 2 minutes (listing up to 5 services) and another happens every 60 minutes (listing up to 20 services).  These traces provide the total time for all the requests against that service along with the number of requests and its average request time.  This information can provide a good start in possibly troubleshooting performance issues or tracking a particular issue.   [Read More] 

    Read the article

  • How long does an ext4 format take?

    - by Bill O'Dwyer
    The USB cable on my Iomega Prestige 1TB hard drive conked out a while back, and I've finally managed to get a new one. I removed the old NTFS file system because I use Windows maybe once a month, and then only for Windows-only activities. So I plug in the HDD to my laptop, and get it to start converting to ext4. Gparted is currently on the "create new ext4 file system" and has been for about 2 hours. Is this right? I know 1TB is fairly large, but the last time I did this, I'm pretty sure it was a fast(er) job.Can anybody shed some light on what's going on here?

    Read the article

  • SQL SERVER Introduction to Extended Events Finding Long Running Queries

    The job of an SQL Consultant is very interesting as always. The month before, I was busy doing query optimization and performance tuning projects for our clients, and this month, I am busy delivering my performance in Microsoft SQL Server 2005/2008 Query Optimization and & Performance Tuning Course. I recently read white paper about Extended [...]...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

    Read the article

  • Why isn't this rewrite rule (nginx) applied? (trying to setup Wordpress multisite)

    - by Brian Park
    Hi, I'm trying to setup Wordpress multisite (subfolder structure) with nginx, but having a problem with this rewrite rule. Below is the Apache's .htaccess, which I have to translate into nginx configuration. RewriteEngine On RewriteBase /blogs/ RewriteRule ^index\.php$ - [L] # uploaded files RewriteRule ^([_0-9a-zA-Z-]+/)?files/(.+) wp-includes/ms-files.php?file=$2 [L] # add a trailing slash to /wp-admin RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L] RewriteCond %{REQUEST_FILENAME} -f [OR] RewriteCond %{REQUEST_FILENAME} -d RewriteRule ^ - [L] RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L] RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L] RewriteRule . index.php [L] Below is what I came up with: server { listen 80; server_name example.com; server_name_in_redirect off; expires 1d; access_log /srv/www/example.com/logs/access.log; error_log /srv/www/example.com/logs/error.log; root /srv/www/example.com/public; index index.html; try_files $uri $uri/ /index.html; # rewriting uploaded files rewrite ^/blogs/(.+/)?files/(.+) /blogs/wp-includes/ms-files.php?file=$2 last; # add a trailing slash to /wp-admin rewrite ^/blogs/(.+/)?wp-admin$ /blogs/$1wp-admin/ permanent; if (!-e $request_filename) { rewrite ^/blogs/(.+/)?(wp-(content|admin|includes).*) /blogs/$2 last; rewrite ^/blogs/(.+/)?(.*\.php)$ /blogs/$2 last; } location /blogs/ { index index.php; #try_files $uri $uri/ /blogs/index.php?q=$uri&$args; } location ~ \.php$ { include /etc/nginx/fastcgi_params; fastcgi_pass 127.0.0.1:9000; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME /srv/www/example.com/public$fastcgi_script_name; } # static assets location ~* ^.+\.(manifest)$ { access_log /srv/www/example.com/logs/static.log; } location ~* ^.+\.(ico|ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|css|rss|atom|js|jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi|wav|bmp|rtf)$ { # only set expires max IFF the file is a static file and exists if (-f $request_filename) { expires max; access_log /srv/www/example.com/logs/static.log; } } } In the above code, I believe rewrite ^/blogs/(.+/)?(.*\.php)$ /blogs/$2 last; has no effect because when I look at the access_log file, I see the following line: 2010/09/15 01:14:55 [error] 10166#0: *8 "/srv/www/example.com/public/blogs/test/index.php" is not found (2: No such file or directory), request: "GET /blogs/test/ HTTP/1.1" (Here, 'test' is the second blog created using multisite feature) What I'm expecting is that /blogs/test/index.php gets rewritten to /blogs/index.php, but it doesn't seem to do that... Am I overlooking something obvious? Thanks!

    Read the article

  • My colleague can't visit our website through her provider after long downtime

    - by Peter Westerlund
    We did a frontpage update some days ago that caused the site to crash. The site was down for several hours. After troubleshooting, we concluded that we needed to cache more content. It had been run too many queries. After solving that and rebooting of server, we here in Sweden and Norway were again able to visit the site. But a colleague in Tunisia couldn't. It seems to work from another internet provider but not her own. What could have happened? And what should we do? Edit: I should add: She is able to visit the site through tunnel at anonymouse.org.

    Read the article

< Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >